KR100411475B1 - Method for manufacturing capacitance type pressure sensor and pressure detecting device by using the same - Google Patents

Abstract

The present invention provides a method of manufacturing a capacitive pressure sensor that accurately detects the pressure of a fluid / gas flowing in a pipeline to facilitate the manufacture of a pressure sensor, and provides a pressure detection device using the same to improve accuracy in pressure detection. The present invention relates to a manufacturing method of a capacitive pressure sensor and a pressure detecting device using the same,

The present invention relates to a first process of forming a housing by processing a metal material, a second process of welding an insulating material (glass) to the housing to form an insulation portion, and a process of processing the insulation portion into a curved surface and forming an oil passage in a central portion thereof. A third step of lapping the end face of the insulating part processed into a curved surface; a fifth step of washing after lapping and drying to remove moisture; and a second step of depositing electrodes by melting aluminum in a vapor state on the surface of the insulating material. By manufacturing a pressure sensor through a sixth step, a seventh step of welding the sensing plate and the insulating plate, an eighth step of filling the oil passage with silicon oil, a closing of the oil filling hole, and a ninth step of welding the sensor housing, It offers ease of manufacture of pressure sensors and ensures accuracy in pressure detection.

Description

Method for manufacturing capacitance type pressure sensor and pressure detecting device by using the same}

The present invention relates to a capacitive pressure sensor and a pressure detecting device using the same, and more particularly, to a method of manufacturing a capacitive pressure sensor for accurately detecting the pressure of a fluid / gas flowing in a pipeline and a pressure detecting device using the same. It is about.

In general, one of the indispensable instrumentation instruments for automation / energy in the industrial field is the pressure detection device.

Such a pressure detecting device is a device for detecting a flow of a fluid / gas flowing in a conduit.

However, many sensors and devices for detecting the flow of fluids / gases in a pipeline have been proposed in the related art, but the structure is so complicated that it is difficult to manufacture, and in particular, it is difficult to measure accurate pressure detection. .

Accordingly, the present invention provides a method of manufacturing a capacitive pressure sensor that accurately detects the pressure of a fluid / gas flowing in a pipe line, thereby facilitating the manufacture of a pressure sensor, and providing a pressure detecting device using the same. An object of the present invention is to provide a method of manufacturing a capacitive pressure sensor and a pressure detecting device using the same.

"Method of manufacturing capacitive pressure sensor" according to the present invention for achieving the above object,

A first step of forming a housing by processing a metal material;

A second step of forming an insulating part by welding an insulating material (glass) to the housing;

A third step of processing the insulating portion into a curved surface and forming an oil passage in a central portion thereof;

A fourth step of wrapping a cross section of the insulated portion processed into the curved surface;

A fifth step of performing washing after lapping and drying to remove moisture;

A sixth step of depositing electrodes by melting aluminum in a vapor state on the surface of the insulating material;

A seventh step of welding the sensing plate and the insulating plate;

An eighth step of filling the oil passage with silicone oil;

Finishing the oil filling hole, and characterized in that the manufacturing including the ninth process of welding the sensor housing.

In addition, the "pressure detection apparatus using the capacitive pressure sensor" by this invention,

A pressure sensor for generating a capacitance signal corresponding to the pressure of the fluid / gas flowing in the conduit;

A capacitive / frequency converting unit converting the capacitive signal output from the pressure sensor into a frequency signal;

An analog / digital converter for converting the frequency converted by the capacitance / frequency converter into a digital signal corresponding thereto;

A central processing unit for comparing the detection data output from the analog / digital converter with parameters previously stored in the ypyrom to determine a pressure state, and outputting control data for transmitting and displaying the determined pressure state data;

A digital / analog converter converting the pressure detection data output from the central processing unit into an analog signal and transmitting the analog signal to a display side;

And a communication processor transmitting the pressure detection data output from the central processing unit to an external device.

1 is a view showing the structure of a capacitive pressure sensor according to the present invention,

2 is a process flowchart showing a method of manufacturing a capacitive pressure sensor according to the present invention;

3 is a block diagram showing the configuration of a pressure detection device using a capacitive pressure sensor according to the present invention.

<Explanation of symbols for the main parts of the drawings>

100 ..... Pressure sensor

101 ..... Housing

102 ..... Insulation (Glass)

105, 106 ..... electrode

200 ..... Capacitive / Frequency Converter

300 ..... analog to digital converter

400 ..... Central Processing Unit

500 ..... Ypyrom

600 ..... digital to analog converter

700 ..... Communication Processing Unit

Hereinafter, a preferred embodiment of the present invention according to the technical spirit as described above will be described in detail with reference to the accompanying drawings.

2 is a process flowchart showing a method of manufacturing a capacitive pressure sensor according to the present invention.

As shown therein, a first step of forming a housing by processing a metal material (S101); A second step (S102) of forming an insulating part by welding an insulating material (glass) to the housing; A third step (S103) of processing the insulating part into a curved surface and forming an oil passage in a central portion thereof; A fourth step (S104) of wrapping a cross section of the insulated part processed into the curved surface; Performing a washing after the lapping and drying to remove moisture (S105); A sixth step (S106) of depositing an electrode by melting aluminum in a vapor state on the surface of the insulating material; A seventh step (S107) of welding the sensing plate and the insulating plate; An eighth step (S108) of filling the oil passage with silicone oil; Finishing the oil filling hole, and the ninth process (S109 ~ S110) of welding the sensor housing.

Figure 2 shows the structure of the capacitive pressure sensor manufactured by the present invention.

Hereinafter, a method of manufacturing a capacitive pressure sensor will be described in detail with reference to FIGS. 1 and 2 as follows.

First, in step S101, a groove is processed to make an insulator in a special metal material having the smallest coefficient of thermal expansion, thereby making the housing 101. Next, in step S102, a ceramic-based insulating material (high purity glass) 102 having a small change in dielectric constant is welded to a groove formed in the housing 101 to form an insulating part, and in step S103, surface corrosion and dimensional variation due to high temperature heat are changed. As a result, the curved surface of the insulating diaphragm is processed, and the passage 103 of the silicon oil 104 is formed in the center portion.

This structure widens the distribution during pressurization, allowing the sensor to operate safely, and gives a delay in time during depressurization, thereby improving detection characteristics.

In addition, the end of the passage of the oil is formed at intervals of 90 or 30 degrees to secure the flow path. In this way, the oil responsiveness can be improved by freeing the movement of the oil.

Next, in step S104, the formed curved surface is precisely processed (cross section lapping) using a diamond wheel.

Thereafter, the washing is performed in step S105, and drying is performed for a predetermined time on a foot to put a compartment into a dryer to remove water after washing.

Subsequently, in step S106, the electrode 1050 (106) is deposited in a process of melting aluminum in a vapor state onto a surface of the insulating material 102 in a vacuum chamber and coating it on a workpiece.

After depositing the electrodes 105 and 106, the conductive wires 107 and 108 are connected to the respective electrodes.

Next, in step S107, the sensing plate 109 and the insulating plate of 0.02mm are welded. Here, after welding the sensing plate 109 and the insulating plate, LEAK TEST is performed to check the vacuum state of the sensor.

In practice, the pressure sensor according to the present invention manufactures two housings in the same manner as described above, and sandwiches the two to sandwich the metal plate 109 having a thickness proportional to the magnitude of the pressure therebetween and maintains hermetic precision. Do it.

In addition, the silicon oil 104 is filled in step S108. In operation S109, the oil filling hole HOLE is finished.

After the filling hole is finished, the hysteresis is checked by repeating pressurization and depressurization at a predetermined pressure of each type, and an overpressure test is performed by applying 150% of a constant pressure of each type of CELL. If the test is determined to be normal after such a test, the completed cell in step S110 is welded to the housing 101 to manufacture a pressure sensor.

In FIG. 2, reference numeral 110 denotes a stainless steel curved plate of 0.05 mm welded to the outermost portion of the sensor housing 101, and reference numeral 111 denotes a portion for finishing the oil filling hole. Reference numeral 112 denotes a common electrode, and reference numeral 113 denotes a temperature detector for detecting the temperature of the pressure sensor in order to keep the temperature of the pressure sensor constant.

In the pressure sensor manufactured as described above, when the pressure of the fluid is applied, the applied pressure is pressed by a plate made of 0.03 ton metal, and the amount (force) of the pressed pressure is transmitted by the silicone oil 104, The sensing plate 109 is pressed. At this time, the electrical capacity is changed at the curved portion, and the changed capacitance is proportional to the pressure, and when the converted capacitance is converted / operated into an electrical signal, the pressure can be accurately measured.

FIG. 3 is a block diagram showing an apparatus for detecting an actual pressure state using a pressure sensor manufactured by the above method.

As shown here, the pressure sensor 100 for generating a capacitance signal corresponding to the pressure of the fluid / gas flowing in the pipeline; A capacitance / frequency converting unit 200 for converting the capacitance signal output from the pressure sensor 100 into a frequency signal; An analog / digital converter 300 for converting the frequency converted by the capacitance / frequency converter 200 into a digital signal corresponding thereto; The central processing unit compares the detection data output from the analog-to-digital converter 300 with the parameters previously stored in the ypyrom 500 to determine the pressure state, and outputs control data for transmitting and displaying the determined pressure state data. Device 400; A digital-to-analog converter 600 converting the pressure detection data output from the central processing unit 400 into an analog signal and transmitting the analog signal to a display side; The communication processor 700 transmits the pressure detection data output from the CPU 400 to an external device.

The vacuum detection device using the pressure sensor according to the present invention configured as described above,

Although not shown in the drawing, the DC power input from the power supply is processed to supply driving power for each stage of the apparatus.

Next, when the power is supplied, the pressure sensor 100, as is well known, when the pressure of the fluid is applied, the applied pressure is pressed by a plate made of a metal of 0.03t, the amount (force) Silver is transmitted by the silicone oil 104, and the sensing plate 109 is pressed. At this time, the electrical capacitance is changed in the curved portion, and transmits the change signal of the capacitance to the capacitance / frequency converter 200.

The capacitive / frequency converting unit 200 converts the delivered capacitance signal into a frequency signal corresponding thereto and transmits the converted capacitance signal to the analog / digital converter 300.

In this case, the capacitance / frequency converting unit 200 also maintains a constant temperature of the pressure sensor according to the temperature detected by the temperature detector 113 shown in FIG. 2.

The analog-to-digital converter 300 converts the transmitted analog frequency signal into a digital signal corresponding thereto and transmits the converted analog signal to the central processing unit 400.

The CPU 400 determines a pressure state by comparing various parameter information stored in the YPROM 500 and detection data transmitted from the analog-to-digital converter 300. That is, the pressure value is to be extracted.

In order to transmit the extracted pressure value to an external device, the central processing unit 400 transmits the detected pressure value to the communication processing unit 700, and digitally displays the detected pressure value to display the detected pressure state. It transfers to the analog converter 600.

The communication processor 700 transmits the transmitted pressure value to an external device through a communication line, and the digital / analog converter 600 converts the transmitted digital pressure data into an analog signal corresponding thereto. Although not shown in the drawing, the detected pressure value is displayed by being transmitted to a display device at a later stage.

For reference, in the present invention, communication is performed in a manner called HART PROTOCOL, and this pyrom stores information such as linearity processing, use range information, sensor identification number data, room temperature compensation information, sensor abnormal state check signal, and the like. If necessary, the central processing unit uses the stored information to perform the corresponding function.

According to the "manufacturing method of the capacitive pressure sensor and the pressure detecting device using the same" according to the present invention described above, there is an advantage of providing a capacitive pressure sensor that is easy to manufacture and precise pressure measurement.

In addition, by providing a pressure detection device using such a pressure sensor, there is an advantage that can accurately measure the pressure.

Claims (2)

A first step of forming a housing by processing a metal material; A second step of forming an insulating part by welding an insulating material (glass) to the housing; A third step of processing the insulating portion into a curved surface and forming an oil passage in a central portion thereof; A fourth step of wrapping a cross section of the insulated portion processed into the curved surface; A fifth step of performing washing after lapping and drying to remove moisture; A sixth step of depositing electrodes by melting aluminum in a vapor state on the surface of the insulating material; A seventh step of welding the sensing plate and the insulating plate; An eighth step of filling the oil passage with silicone oil; A method of manufacturing a capacitive pressure sensor, comprising the ninth process of finishing the oil filling hole and welding the sensor housing. A pressure sensor for generating a capacitance signal corresponding to the pressure of the fluid / gas flowing in the conduit; A capacitive / frequency converting unit converting the capacitive signal output from the pressure sensor into a frequency signal; An analog / digital converter for converting the frequency converted by the capacitance / frequency converter into a digital signal corresponding thereto; A central processing unit for comparing the detection data output from the analog / digital converter with parameters previously stored in the ypyrom to determine a pressure state, and outputting control data for transmitting and displaying the determined pressure state data; A digital / analog converter converting the pressure detection data output from the central processing unit into an analog signal and transmitting the analog signal to a display; Pressure detection device using a capacitive pressure sensor, characterized in that it comprises a communication processor for transmitting the pressure detection data output from the central processing unit to an external device.